18GW was established officially on 01st December 2008 to directly involve the humanitarian operation since 2008 to 2009 under the command of 641BDE. In this period good leadership and guidance was given by the first commanding officer LT COL MARB FERNANDO RWP RSP.
18GW advanced from ETHAWETUNUWEWA to ODDUSUDAN till they reach A-34 road. The LTTE made a huge earth bunt as a obstacle to enter the ODDUSUDDAN town. The infantry troops had to take huge risk and hardship to enter the area. The LTTE covered the approach by laying minefields.
When the troops confronting, According toThe officer commanding of D Coy Lt DLM Arachchige direction & leadership the troops had to cross the open area through marshy. At this moment LTTE launched a surprise attack by using heavy volume of fire power. During that confrontation land 4 soldiers made supreme sacrifice of their Lives for the mother land. 4 officers and few soldiers got wounded in action.
On 16thMarch 2009 18GW was directed to capture the earth bunt near to the PUDUKUDUIRIPPU town. Soldiers launched massive attack and captured the earth bunt. In this attack 30-40 LTTE carders were killed and 07 RPGS, 02 T-56 were captured by the soldiers. 01 0fficer and 07 other rankers got injured.
The Battalion committed the operation from ETHAWETUNAWEWA, WELIOYA to NANDIKADAL lagoon. During this operation 01 officer and 31 other rankers made the supreme sacrifice to safeguard the unity, sovereignty and territorial integrity of the motherland. 01 officer and 190 other rankers were wounded during that battle.
After the successful operation, on 1stJune 2009 Bn was deployed in MULANKAVIL jungle area, under 651BDE in SFHQ (KLN). Thereafter Battalion secures the area and launched small group operation in that area.
On 25th AUG 2009, 18GW deployed at KOVILAKKANDI in JAFFNA, under 523BDE to secure the area and facilitated the infrastructure facilities in resettlement of civilians.
Presently18thBattalion The Gemunu Watch is located in Dambegoda Maligavila under 121Bde.
Former Commanding Officers:
| Srl No | Rank | Name | From | To |
| 1 | Lt Col | MARB Fernando | 2008.12.25 | 2011.01.14 |
| 2 | Lt Col | BASSD Bulathgama | 2011.01.14 | 19.11.2013 |
| 3 | Lt Col | GDSM Alwis | 2013.11.19 | 2016.02.09 |
| 4 | Lt Col | R R De S Dharmawikrema RSP | 2016.02.10 | 2018.02.18 |
| 5 | Lt Col | S J M N S Perera USP | 2018.02.19 | 2020.02.19 |
| 6 | Lt Col | AMDK Abeykoon RWP RSP USP psc | 2020.02.20 | 2021.12.26 |
| 7 | Maj | RM Pathiraja RSP USP | 2021.12.27 | Up to Date |
